Oldupai

Unknown to non-Africans before the colonial period, the prehistory of the interior of Africa has since been partly pieced together. Discovered by chance in 1910 by a German entomologist who stumbled across some fossils and bones, evidence of human life was found in Tanzania's Olduvai Gorge and the place attracted the attention of Professor Leakey and his wife, whose names are forever linked to the site. Their research started in 1931 but it was not until 1959 that MaryLeakey found fragments of teeth and a skull which were part of a male hominid whom they called Zinjanthropus or Nutcracker Man, because of his huge teeth. The skull was dated to be 1.75 to 2 million years old and was proof that hominids inhabited the area; it shifted the centre of human evolution from Asia to Africa and the discovery 20 years later of footprints at Laetoli south of Olduvai pushed back the presence of hominids to 3.5 to 4 million years.

The man who mended the clutch

After this brief reconnaissance [to Laetoli] they returned to Olduvai to find that the pool which they had been using for their water had turned to mud and become the property of a resident Rhino, who used it for his daily ablutions. Worse still, in order to keep the wallow moist he urinated into it freely. More inviting water supplies were available both at the spring at Olmoti and at Ngorongoro, but petrol was too short to be used for this purpose. They tried to collect rain water off the roofs of the tents, forgetting that the canvas had been impregnated with insecticide; there were dire results, and all the party were violently ill after drinking the water. By this time they were also running short of food. SamWhite and PeterBell were due to return to England, and the lorry taking them back to Nairobi was to bring much needed supplies to the garrison at Olduvai; but it never returned.

For the next fortnight Louis and Mary's diet consisted almost entirely of rice and sardines. An even greater hardship was the lack of cigarettes, and they had to resort to picking up fag ends scattered round the camp. When the lorry failed to appear after two weeks they set out to look for it. At one point they had to turn back as the road was in such a terrible state, and they spent the rest of the day helping to extract Indian traders' lorries from the mud. Their reward was a little flour and sugar, but they were still very hungry. Next their own car overturned in a gully, and they spent a whole day trying to extricate it with a plate and some spoons. (The lack of proper tools seems curiously uncharacteristic of Louis, who was usually so efficient.) Watching their efforts was a crowd of supercilious Masai warriors who considered it beneath their dignity to do any manual labour. It was just as well that Louis did not try to press them: almost at that very moment the District Commissioner at Narok was being murdered by Masai for ordering them to help with road work. Louis and the Masai treated each other with mutual respect, and many of them had cause to be grateful for the treatment they received at the clinics he ran at Olduvai.

The lorry turned up just in time to pull the car back on to the road - its delay had been caused by clutch trouble. (By a curious coincidence the man who mended the clutch at the Motor Mart in Nairobi became Mary's nearest neighbour at Olduvai thirty-five years later: he is GeorgeDove, a 'character' with magnificent waxed moustachios who ran a delightful little tourist lodge at Ndutu, some thirty miles from Olduvai, in the early 1970's.) The car itself was in far worse condition than the lorry had been, with the whole of the bodywork damaged, but amazingly it was still able to run. Louis and Mary returned to Olduvai to pack up before setting off for their next target, a place called Engaruka.

The world heard about the footprints

For several decades Laetoli had just missed as a hominid fossil site. LouisLeakey had a try there in 1935, but came up emptyhanded. He did not know that a tooth he had sent to the British Museum labeled as a baboon's was a hominid canine. Not only was it the first adult australopithecine tooth ever found, but it was the first of any kind since the discovery of the Taung Baby. Nevertheless, it lay unnoticed in the Museum collection until 1979, when it was spotted and properly identified by White.

Leakey, meanwhile, not realizing that he had had in his hand the oldest hominid fossil then known, packed up and moved to Olduvai. He was followed at Laetoli in 1938-1939 by a German named Kohl-Larsen, who recovered a bit of an upper jawbone with a couple of premolars in it, and a well-preserved alveolus - or socket - for a canine tooth.

The trouble with those early Laetoli finds was that they were far too old and far too primitive for anyone then to dream that they were not apes or monkeys; the imagination of the 1930s was simply not elastic enough to accommodate them, even though that same imagination was saying to itself, 'Look deeper into time for older ancestors.' This is an odd, schizophrenic view that still persists today.

By 1974, when MaryLeakey decided to have a go at Laetoli, her mind at least was ready to recognize and accept very old specimens of Homo. When one of the Leakey-trained Kenyan field experts, KarnoyaKimeu, took it upon himself to cut a road in to the deposits through the thicket and came out with a hominid, MaryLeakey moved in with a team of her own. In the next couple of years she or her workers found forty-two teeth, some of them associated with bits of jawbone. One in particular, LH-4 (Laetoli Hominid 4), was a fine specimen, a mandible with nine teeth in place.

But what sets Laetoli apart from every other site in the world is some footprints that have been found there, certainly one of the most extraordinary cases of preservation and discovery in all of paleoanthropology.

Laetoli has a nearby volcano, Sadiman, that is extinct today. Not quite four million years ago it was active. One day it spat out a cloud of carbonitite ash. This stuff has a consistency not unlike that of very fine beach sand, and it powdered down over the surrounding landscape in a layer that reached a thickness of about half an inch before the eruption stopped. This fall of superfine cinders must have been extremely unpleasant for the local animals and birds while it was coming down, but there is no evidence that it did more than make them uncomfortable, because they stayed in the area. That first puff of ash - probably not lasting more than a day - was followed by a rain. The ash became wet and, almost like a newly laid cement sidewalk, began taking clear impressions of everything that walked across it: elephants, giraffes, antelopes, hares, rhinos, pigs. There were also terrestrial birds like guinea fowl and ostriches, and even the small tracks of millipedes.

In the hot sun of Laetoli the wet ash layer quickly dried and hardened, preserving the footprints that crisscrossed it. Then, before it could rain again, Sadiman spoke a second time. Another cloud of ash drifted down, covering the first and sealing in the footprints. This happened a number of times over a period estimated to have been no longer than a month, producing a single volcanic tuff about eight inches thick. .But because of the periodic puffing of Sadiman and the periodic hardening of the ash that fell, the tuff is actually composed of between a dozen and two dozen distinct thin layers. Some of these layers have been exposed recently by erosion, and are visible here and there at Laetoli in the form of a gray substrate wherever the mat of coarse turf above them has been carried off.

One afternoon in 1976, some of the more boisterous members of MaryLeakey's field team were amusing themselves by throwing hunks of dried elephant dung at each other. This may seem a peculiar pastime, but recreational resources are limited on paleontological digs, and there are times when young spirits need to blow off steam. One who felt this urge was AndrewHill, a paleontologist from the National Museum of Kenya, who, while ducking flying dung and looking for ammunition to fire back, found himself standing in a dry stream bed on some exposed ash layers. One of these had some unusual dents in it. When Hill paused to examine them, he concluded they probably were animal footprints. That diagnosis was confirmed when a larger area was surveyed and other prints found. But no serious effort was made to follow up this extraordinary discovery until the following year, 1977, when a number of large elephant tracks were found by MaryLeakey's son Philip and a co-worker, PeterJones, and alongside them some tracks that looked suspiciously like human footprints.

The world heard about the footprints later that year when MaryLeakey came to the United States to report on them in a series of press conferences and interviews. To many it seemed almost inconceivable that anything so ephemeral as a footprint should have been preserved for so long. But Mary was positive about the hominid ones. She went on to describe the latter as having been made by a creature that was an imperfect walker; the prints indicated that it had shuffled. She also reported the probable presence at Laetoli of knuckle-walking apes and the existence of a water hole around which the animals and birds appeared to have clustered. She even saw some evidence of panic in the tracks, suggesting that the animals had been fleeing the eruption.

Those revelations by MaryLeakey electrified everybody who heard them. She resolved to devote much of the next season's effort at Laetoli to footprints, and asked the American footprint expert LouiseRobbins to join her team. White went to the Laetoli site for the first time that year, and found three other young scientists there: PeterJones, PaulAbell and RichardHay. These men had some doubts about Mary's interpretation of the footprints. White questioned the presence of knuckle-walking apes; he had examined those prints and said that they had been made by large extinct baboons that walked flat-footed. Jones said there had been no panicky exodus from the area, because birds, which could have flown away easily and quickly, continued to walk about in the ash it was crisscrossed with their tracks. Hay could find no evidence of a water hole.

These disagreements made for a good many nights of heated argument in camp, during which the supposedly human footprints had their ups and downs. No one could agree on them. Then PaulAbell, prospecting alone one day, found a broken impression - but a much clearer one - that he said he was quite confident was a hominid print. White and Jones made some Polaroid shots of it and came back with a strong impression that Abell was right. They recommended that excavation in the area be started immediately. But LouiseRobbins, the footprint expert, examined it and declared that it was the print of a bovid (a hoofed animal). She told MaryLeakey that further investigation would be a waste of time. The men objected.

By then MaryLeakey had become thoroughly exasperated by all the arguing that had been going on. She announced that there would be no excavation. Jones, now convinced that it was a hominid, continued to plead with her for permission to make an excavation. A very small one, he said, was all he asked. Mary was adamant. LouiseRobbins, the authority, had spoken; there was too much incomplete excavation at the site already. If there was going to be any digging, let it be done by somebody who had nothing better to do. She pointed to Ndibo, the maintenance man, the man in camp with the least archeological training.

Ndibo, however, proved equal to the task. He returned to camp the next day and reported not one, but two footprints. One was very large. He held his hands up, about a foot apart.

'Those Africans are always exaggerating,' said Mary. But she did go out to have a look, and there they were. White was permitted to start an excavation.

The direction of the prints indicated that their maker had been walking north under some sections of turf that had not yet been eroded. Because of the dense tangle of roots at the bottom of the turf, the task of exposing a clear ash surface without destroying it - not to mention the exact ash out of a dozen or more thin layers of it turned out to be extraordinarily difficult. But Tim is an extraordinarily patient and determined man. He found another print, and then another. He proceeded to protect the prints by hardening them with a preservative, which he poured into them in very small amounts, letting the material dry and then strengthening it by adding more. Working with agonising slowness, he inched his way farther and farther into the turf and discovered that the trail consisted of the tracks of two hominids.

Now he had the riveted attention of the entire camp. Others joined the work and ultimately were able to reveal more than fifty prints covering a distance of seventy-seven feet. LouiseRobbins, her interest in the footprints suddenly rekindled, issued another opinion: indeed there were two hominids; they were probably walking together; one (with slightly larger prints) was a male; the other, possibly pregnant she said, was a female; on the evidence of the prints, this type of hominid had been an erect walker for at least a million years.

These are entertaining speculations. There is no way of telling what sex the makers of the footprints were, if one was pregnant, or how long their ancestors had walked erect. The hard truth is that 3.7 million years ago erect hominids of indeterminate sex did walk through fresh-fallen ash at Laetoli and leave an imperishable record of their passing. After seventy-seven feet their trails disappeared under the overlying ash; the particular layer that marked it has been washed away. Tim's work on the footprints stopped at that point, which also marked the end of the season. But he felt strongly that the trail could be picked up again a little farther along and that it would yield more prints if proper excavation were carried out. Work in that direction was done in 1979 by Ron Clarke, and the trail picked up again.

Tim was not a party to this further work. His arguments with LouiseRobbins over interpretation of the footprints have made him as unwelcome now at Laetoli as he is at Lake Turkana - a pity, because in each instance he was only trying to help the proprietors.

Tim's concern today is that as more prints are found, they be handled with the utmost care. They are supremely fragile, and the slightest mistake in excavating them can destroy them completely. Some have already been damaged. They are not like fossils, those rocklike models of durability. They are only spaces, mere shapes in a relatively soft and frangible matrix. If that matrix is nudged incorrectly, it will crumble - and the footprints will be gone.

But, by a wildly improbable linkage of random events, they are there. Sadiman had to blow out a particular kind of ash. Rain had to fall on it almost immediately. Hominids had to follow on the heels of the rain. The sun had to come out promptly and harden their footprints. Then another blast from Sadiman had to cover and preserve them before another obliterating shower came along.

All this had to happen over a period of only a few days. And the volcano had to synchronise its activity with that of the seasons. If its bursts had not come just when they did - at the beginning of the rains - the footprints would not have been preserved. A month or two earlier, during the dry season, the ash would not have had the consistency to take a sharp imprint. It would have been a hopelessly blurry one, a mere dent, like the one a passerby today makes in the dry sand on the upper margin of a beach. If it had come later, at the height of the rainy season, it is overwhelmingly likely that there would have' been too much rain; the footprints would have been washed away before they could have been baked hard by the sun. Indeed, there had to be just what the beginning of a rainy season produces: sporadic showers interspersed with intervals of hot sun.

All things considered, the preservation and recovery of the Laetoli footprints are nothing short of a miracle. They confirm without a shadow of a doubt what Lucy confirmed at Hadar: that hominids were fully erect walkers at three million B.C. and earlier. At Hadar the evidence is in the fossils, in the shape of leg and foot bones. But at Laetoli, where the fossil remains - some extremely scrappy and enigmatic postcranial bits, jaw parts, and some teeth - are of very poor quality, there is no way without the footprints of deducing how those hominids got around.

'Make no mistake about it.' says Tim. 'Thev are like modern footprints. If one were left in the sand of a California beach today, and a four-year-old were asked what it was, he would instantly say that somebody had walked there. He wouldn't be able to tell it from a hundred other prints on the beach, nor would you. The external morphology is the same. There is a well-shaped modern heel with a strong arch and a good ball of the foot in front of it. The big toe is straight in line. It doesn't stick out to the side like an ape toe, or like the big toe in so many drawings you see of australopithecines in books.

I don't mean to say that there may not have been some slight differences in the foot bones; that's to be expected. But to all intents and purposes, those Laetoli hominids walked like you and me, and not in a shuffling run, as so many people have claimed for so long. Owen Lovejoy deduced all that from studying the Hadar bones. Now the footprints prove him right. I think they rank with the most wonderful and illuminating discoveries in decades. Although it didn't end too happily for me, I'm still grateful that. I was lucky enough to have participated in the work on them.'

Discovers Zinjanthropus

Although she enjoyed this artistic interlude to her career, Mary soon found herself back in the dirt, this time excavating in Olduvai Gorge in northern Tanzania. Louis had first visited the gorge in 1931 and was overwhelmed by the wealth of archaeological material existing there, but for many years he lacked the money to initiate a proper excavation. Finally, in 1951, with some monetary assistance from CharlesBoise, the Leakeys were able to establish a base camp and begin their investigations.

The next seven years brought steady progress but no incredible finds. Then, the morning of July 17, 1959, Mary was walking through site FLK with her Dalmatians (Louis was sick at camp with the flu), when she caught sight of what looked like a hominid skull protruding from the ground. On closer investigation, she saw that two teeth were still intact in the upper jaw and that everything appeared in situ. She'd discovered "Zinjanthropus" (later named Australopithecus Boise). Scientists agree that "Zinj" is on an evolutionary side branch-not a direct human ancestor; however, the 1.75-million-year-old specimen was the first of his species ever found, and at the time of his discovery, the oldest hominid. Mary says in her autobiography, "two major discoveries marked turning points in my life, the finding of Proconsul in 1948, and the finding of Zinj in 1959."

Rhinos at Oldupai

... I have rejected some of the wilder statements concerning the killing of Rhino in and around Ngorongoro, particularly one by ElspethHuxley in Forks and Hopes, published 1963,:

'The Olduvai Gorge used to be full of Rhino. And then, in 1961, in the space of six months, the Leakeys counted over fifty rotting carcases in the Gorge, all speared by Masai. Whether or not their motive was political, they had taken the profit; every horn had been removed.

Since then the Leakeys have not seen a single Rhino at Olduvai.'

This demonstrably false account is unfortunately typical of the wildlife 'crusaders' and illustrates how a good case can be discredited by exaggeration. JohnGoddard's work has shown that the gorge was inhabited (1966) by over 70 Rhino. With an animal of such static habits it is clearly impossible that the population built up from nil to 70 between 1963, when ElspethHuxley was writing, and 1966.

Dian Fossey's first Safari

Alexander set up his safari operation at his home near Nanyuki. John was flexible enough to tailor safaris exactly to the needs and pockets of his clients. One of his clients was near stone broke DianFossey, who much later attained recognition as a gorilla expert. In 1963DianFossey was staying at the Mount Kenya Safari Club at Nanyuki, and she introduced herself to one of the owners of the club, William Holden. Fossey told Holden she was looking for a white hunter to take her on a private safari through East Africa. Was there someone he might recommend? Holden knew a man on the mountain he thought might be suitable named JohnAlexander. Fossey talked John into a you-bring-the-coffee, I'll-bring-the-sandwiches low-budget outing. When starry-eyed Fossey first met Alexander, then fortyish, she was the ultimate naive greenhorn in the wilds of Africa.

John, his complexion now ruddy from years in the sun, and his fair hair by now receding, had always had an eye for the ladies. Recently divorced, he was not inclined to turn down any safari work. Even with Fossey's limited budget Alexander nevertheless consented to take her on a tour, and guided her on what is generally regarded as the East African "milk run," an easy route taken by package tourists on their first trip to Africa. John took Dian to see Tsavo park, Ngorongoro Crater, the Serengeti Plains, and Olduvai Gorge, where he introduced her to anthropologists Mary and LouisLeakey.

Alexander later recalled Fossey with considerable distaste, not just because she was a heavy smoker and drinker, which he considered none of his business, but because he thought Fossey "moody" and a "bit neurotic." Alexander claimed that at the time of their meeting Fossey had never before even heard of mountain gorillas'

Still, Alexander agreed to take Fossey on another safari, this time through Uganda and into the Congo to the Albert national park (now the Muhuavura national park). In neighboring Rwanda over this period, two tribes, the WaTutsi and the BaHutu, were killing each other in the thousands; the first years of genocide were barely reported to the international press. Zaire was also far from safe, with murderous soldiers roaming the countryside.

Despite the tribal unrest and general chaos then prevalent in Zaire, Alexander and Fossey continued with their safari into the eastern part of the country. At the village of Rumangabo they had hoped to pick up park rangers to act as guides. The only accommodation available was an old shed and it was here Fossey propositioned Alexander. "Here we've been three weeks on safari," she said. "We could have shacked up together and had a hell of a good time. "

Alexander apologetically turned her down explaining that he was already engaged. After being rebuffed Fossey despised Alexander, according to Harold T. P. Hayes, her biographer. Behind his back she began referring to John as "The Great White.""

building the Lodge

Exhibition at Oldupai - visited April 1999.

While building the Lodge, GeorgeDove brought in building materials from Laetoli Gorge and noticed that they included a large number of fosils. Some of these can be seen embedded in the wall of the dining room at Ndutu. George told MaryLeakey about these, and they persuaded her to shift her attention from Oldupai to Laetoli, leading eventually to the discovery of the footprints.

Out of Africa to a better sunset
'Oh dear, isn't . . .

Obituary

'Oh dear, isn't it silly? I just wanted to get a better view of the sunset'. ...

on an impulse [she] took off to tour Africa with a friend. In Kenya she met the archaeologist Louis Leakey; he proposed and she went back to England to think things over. When he returned in 1928, they married and once again left for Africa ... .

Frida became an expert in the drawing of stone tools, but she also worked on Leakey's excavations. Amongst her important finds was a fossil site in Tanzania, a side gully in the Olduvai gorge, later named the FLK, the FridaLeakey Karongo (meaning gully). It was at the FLK that Leakey's second wife, Mary, found the skull of Nutcracker Man, nearly 30 years later.

Mary Leakey: Unearthing History

This profile of Dr. Leakey, written by former news editor Marguerite Holloway, originally appeared in the October 1994 issue of Scientific American.

MaryLeakey waits for my next question, watching from behind a thin curtain of cigar smoke. Leakey is as famous for her precision, her love of strong tobacco--half coronas, preferably Dutch--and her short answers as she is for some of the most significant archaeological and anthropological finds of this century. The latter would have hardly been excavated without her exactitude and toughness. And in a profession scarred by battles of interpretation and of ego, Leakey's unwillingness to speculate about theories of human evolution is unique.

These characteristics have given Leakey a formidable reputation among journalists and some of her colleagues. So have her pets. In her autobiography, "Disclosing the Past," Leakey mentions a favorite dog who tended to chomp people whom the archaeologist didn't like, "even if I have given no outward sign." So as we talk in her home outside Nairobi, I sit on the edge of a faded sofa, smiling exuberantly at her two dalmatians, Jenny and Sam, waiting for one of them to bite me. I quickly note details-- her father's paintings on the wall, the array of silver trophies from dog shows and a lampshade with cave painting figures on it--in case I have to leave suddenly. But the two dogs and soon a cat and later a puppy sleep or play, and Leakey's answers, while consistently private, seem less terse than simply thoughtful.

Leakey first came to Kenya and Tanzania in 1935 with her husband, the paleontologist Louis Leakey, and except for forays to Europe and the U.S., she has been there ever since. During those many years, she introduced modern archaeological techniques to African fieldwork, using them to unearth stone tools and fossil remains of early humans that have recast the way we view our origins. Her discoveries made the early ape Proconsul, Olduvai Gorge, the skull of Zinjanthropus and the footprints of Laetoli, if not household names, at least terms familiar to many.

Leakey was born in England, raised in large part in France and appears to have been independent, exacting and abhorrent of tradition from her very beginnings. Her father, an artist, took his daughter to see the beautiful cave paintings at such sites as Fond de Gaume and La Mouthe and to view some of the stone and bone tools being studied by French prehistorians. As she has written, these works of art predisposed Leakey toward digging, drawing and early history: "For me it was the sheer instinctive joy of collecting, or indeed one could say treasure hunting: it seemed that this whole area abounded in obje cts of beauty and great intrinsic interest that could be taken from the ground."

These leanings ultimately induced Leakey at the age of about 17 to begin working on archaeological expeditions in the U.K. She also attended lectures on archaeology, prehistory and geology at the London Museum and at University College London. Leakey says she never had the patience for formal education and never attended university; she never attended her governesses either. (At the same time, she is delighted with her many honorary degrees: "Well, I have worked for them by digging in the sun.")

A dinner party following a lecture one evening led her, in turn, to Louis Leakey. In 1934 the renowned researcher asked Mary, already recognized for her artistic talents, to do the illustrations for a book. The two were soon off to East Africa. They made an extraordinary team. "The thing about my mother is that she is very low profile and very hard working," notes Richard E. Leakey, former director of the Kenya Wildlife Service, an iconoclast known for his efforts to ban ivory trading and a distinguished paleontologist. "Her commitment to detail and perfection made my father's career. He would not have been famous without her. She was much more organized and structured and much more of a technician. He was much more excitable, a magician."

What the master and the magician found in their years of brushing away the past did not come easily. From 1935 until 1959 the two worked at various sites throughout Kenya and Tanzania, searching for the elusive remains of early humans. They encountered all kinds of obstacles, including harsh conditions in the bush and sparse funding. Success too was sparse--until 1948. In that year Mary found the first perfectly preserved skull and facial bones of a hominoid, Proconsul, which was about 16 million years old. This tiny Miocene ape, found on Rusinga Island in Lake Victoria, provided anthropologists with their first cranium from what was thought to be the missing link--a tree-dwelling monkey boasting a bigger brain than its contemporaries.

Proconsul was a stupendous find, but it did not improve the flow of funds. The Leakeys remained short of financial support until 1959. The big break came one morning in Olduvai Gorge, an area of Tanzania near the Great Rift Valley that slices East Africa from north to south. Again it was Mary who made the discovery. Louis was sick, and Mary went out to hunt around. Protruding slightly from one of the exposed sections was a roughly 1.8-million-year-old hominid skull, soon dubbed Zinjanthropus. Zinj became the first of a new group--Australopithecus boisei--and the first such skull to be found in East Africa.

"For some reason, that skull caught the imagination," Leakey recalls, pausing now and then to relight her slowly savored cigar or to chastise a dalmatian for being too forward. "But what it also did, and that was very important for our point of view, it caught the imagination of the National Geographic Society, and as a result they funded us for years. That was exciting."

How Zinj fits into the family tree is not something Leakey will speculate about. "I never felt interpretation was my job. What I came to do was to dig things up and take them out as well as I could," she describes. "There is so much we do not know, and the more we do know, the more we realize that early interpretations were completely wrong. It is good mental exercise, but people get so hot and nasty about it, which I think is ridiculous."

I try to press her on another bone of contention: Did we Homo sapiens emerge in Africa, or did we spring up all over the world from different ancestors, a theory referred to as the multiregional hypothesis? Leakey starts to laugh. "You'll get no fun out of me over these things. If I were Richard, I would talk to you for hours about it, but I just don't think it is worth it." She pauses. "I really like to feel that I am on solid ground, and that is never solid ground."

In the field, Leakey was clearly on terra firma. Her sites were carefully plotted and dated, and their stratigraphy--that is, the geologic levels needed to establish the age of finds--was rigorously maintained. In addition to the hominid remains found and catalogued at Olduvai, Leakey discovered tools as old as two million years: Oldowan stone tools. She also recorded how the artifacts changed over time, establishing a second form, Developed Oldowan, that was in use until some 500,000 years ago.

"The archaeological world should be grateful that she was in charge at Olduvai," notes Rick Potts, a physical anthropologist from the Smithsonian Institution who is studying Olorgesailie, a site about an hour south of Nairobi where the Leakeys found ancient stone axes in 1942. Now, as they did then, the tools litter the White, sandy Maasai savanna. The most beautiful ones have been stolen, and one of Leakey's current joys is that the Smithsonian is restoring the site and its small museum and plans to preserve the area.

Olduvai Gorge has not fared as well. After years of residence and work there, and after the death of Louis in 1972, Mary finally retired in 1984. Since then, she has worked to finish a final volume on the Olduvai discoveries and has also written a book on the rock paintings of Tanzania. "I got too old to live in the bush," she explains. "You really need to be youngish and healthy, so it seemed stupid to keep going." Once she left, however, the site was ignored. "I go once a year to the Serengeti to see the wildebeest migrations because that means a lot to me, but I avoid Olduvai if I can because it is a ruin. It is most depressing." In outraged voice, she snaps out a litany of losses: the abandoned site, the ruined museum, the stolen artifacts, the lost catalogues. "Fortunately, there is so much underground still. It is a vast place, and there is plenty more under the surface for future generations that are better educated."

Leakey's most dramatic discovery, made in 1978, and the one that she considers most important, has also been all but destroyed since she left the field. The footprints of Laetoli, an area near Olduvai, gave the world the first positive evidence of bipedalism. Three hominids (generally identified as Australopithecus afarensis ) had walked over volcanic ash, which fossilized, preserving their tracks. The terrain was found to be about 3.6 million years old. Although there had been suggestions in the leg bones of other hominid fossils, the footprints made the age of bipedalism incontrovertible. "It was not as exciting as some of the other discoveries, because we did not know what we had," she notes. "Of course, when we realized what they were, then it was really exciting."

Today the famous footprints may only be salvaged with the intervention of the Getty Conservation Institute. "Oh, they are in a terrible state," Leakey exclaims. "When I left, I covered them over with a mound of river sand and then some plastic sheeting and then more sand and a lot of boulders on top to keep the animals off and the Maasai off." But acacia trees took root and grew down among the tracks and broke them up.

Although Leakey steers clear of controversy in her answers and her writings, she has not entirely escaped it. She and Donald Johanson, a paleontologist at the Institute of Human Origins in Berkeley, Calif., have feuded about the relation between early humans found in Ethiopia and in Laetoli. (Johanson set up his organization as a philosophical counterweight to the L.S.B. Leakey Foundation.) And some debate erupted about how many prints there were at Laetoli. TimWhite of the University of California at Berkeley claimed that there were only two and that Leakey and her crew had made the other track with a tool during excavation. Leakey's response? "It was a nonsense," she laughs, and we are on to the next subject.

A subject Leakey does not like. "'What was it like to be a woman? A mother? A wife?' I mean that is all such nonsense," she declares. Leakey--like many other female scientists of her generation, including Nobel laureates Rita Levi-Montalcini and Gertrude Belle Elion--dislikes questions about being a woman in a man's field. Her sex played no role in her work, she asserts. She just did what she wanted to do. "I was never conscious of it. I am not lying for the sake of anything. I never felt disadvantaged."

Leakey just did her work, surviving bitter professional wars in anthropolog y and political upheavals. In 1952 Louis, who had been made a member of the Kikuyu tribe during his childhood in Africa, was marked for death during the Mau Mau uprising. The four years during the height of the rebellion were terrifying for the country. The brakes on Mary's car were tampered with, and a relative of Louis's was murdered. The house that Leakey lives in today was designed during this time: a low, White square structure with a central courtyard where the dogs can run at night.

These pets are very important to Leakey--a source of companionship and safety out in the bush. She admires the traits in them that others admire in her: independence and initiative. (Any small joy that I have about emerging from her house unbitten fades sadly when I reread the section in her autobiography about her telepathic dalmatian and learn that he died years ago.)

We seem to have covered everything, and so she reviews her discoveries aloud. "But you have not mentioned the fruits," she reminds me. One of Leakey's favorite finds is an assortment of Miocene fossils: intact fruits, seeds, insects--including one entire ant nest--and a lizard with its tongue hanging out. They lay all over the sandy ground of Rusinga Island. "We only found them because we sat down to smoke a cigarette, hot and tired, and just saw all these fruits lying on the ground next to us. Before that we had been walking all over them all over the place." She stops. "You know, you only find what you are looking for, really, if the truth be known."

Olduvai Gorge

Olduvai Gorge, an archaeological site on the Serengeti Plains in northern Tanzania, provides unique evidence for early human evolution and toolmaking from about 2 million to 100,000 years ago. Olduvai was discovered by Wilhelm Kattwinkel, a German entomologist, in 1911. German palaeontologist Hans Reck investigated the gorge after World War I and found the remains of hundreds of extinct Pleistocene mammals but no traces of human tools or primate fossils. The British archaeologist Louis Leakey followed up Reck's work in 1931 and almost immediately found stone tools in the gorge. Leakey, with his wife, Mary, worked at the site intermittently until his death (1972); Mary has continued investigation there.

After years of research the Leakeys began to find prehuman fossils in the gorge. In 1959, Mary Leakey found a skull of Australopithecus boisei, a primitive hominid (humanlike) fossil species, that was later potassium-argon dated to about 1.75 million years before the present. Later a more gracile hominid, called Homo Habilis, was discovered in a level slightly lower than that of the original hominid find. The Homo habilis fragments were said to belong to a larger-brained hominid than Australopithecus and included parts of a hand. A reconstruction of the hand bones revealed an opposable thumb capable of powerful gripping and precise manipulation.

The 1.8-million-year-old skeletal remains of another H. habilis specimen were discovered at Olduvai Gorge in 1986.

The earliest occupation levels at Olduvai date from about 2 million years ago and contain crude Oldowan stone chopping tools with jagged edges as well as the bones of many extinct animals.

Additional hominid fossils have come to light in the lower and the upper (later) levels of Olduvai, including a skull of Homo Erectus dating from about one million years ago. By this time the inhabitants of the Olduvai camps were making more sophisticated stone artefacts of Acheulean type, including carefully shaped stone hand axes that served as more effective multipurpose implements than chopping tools.

Humankindís family tree reshaped

A 1.8-million-year-old jawbone and other fossils uncovered in Tanzaniaís Olduvai Gorge have reignited a longstanding controversy about the family tree of humankindís earliest ancestors. At the same time, the finds offer a new look at how and where early humans lived, according to a study in the journal Science, published by the American Association for the Advancement of Science.

.. .. ..

With FidelisMasao of Tanzania and CharlesPeters of the University of Georgia, Blumenschine co-directs the Olduvai Landscape Paleoarchaeology Project. These researchers focus on stone tools and animal bones bearing butchery marks to reveal the activities of long-ago human ancestors. Fortunately, such specimens occurred in abundance along with OH 65, so the find has shed light on both the evolution and behavior of early humans.

.. .. ..

The work of the Science team in western Olduvai yielded at least one other definitive finding. "The Olduvai Gorge in Tanzania has shown its potential is far from exhausted," wrote erstwhile Leakey colleague Phillip Tobias of South Africaís University of the Witwatersrand, in a commentary that accompanies the Science paper.

Blumenschine agreed: "Thereís a perception that the Leakeys found everything, but thatís the furthest thing from the truth. As long as the Tanzanians continue to treasure and conserve Olduvai, the whole world will continue to be amazed by it."

Tanzania: And the rest is pre-history

The long rains had come to northern Tanzania, and in the night I listened to a constant patter of raindrops magnified by the canvas above my head.

Ndutu Camp was a fine place to be in this season. In the woodlands and marshes of the Olduvai Gorge there were leopards, cheetahs and other wild cats. In the surrounding Serengeti Plains great grazing herds of wildebeest, zebras and gazelles had returned. Along with hyenas, lions and the predators that pursued them, it was a very lively place.

But for the moment I was interested in something a little less lively. It was a good day for fossils.

We drove eastwards out of camp, down the beginnings of the Olduvai Gorge. It had stopped raining, but the track was still slick with mud and muck. We slithered past the shores of Lake Masek, where pink flamingos, their heads plunged in the shallow water, stood feeding in their hundreds. A little further on we stopped and continued on foot.

The bush was sodden, the streams swollen - within minutes we were muddy up to our ankles, grass-soaked above our knees. But then we came to a slope, a space where the ground was open and rocky, and halted.

Hunting for fossils, I discovered, is a bit like hunting for truffles. At first it seems unlikely that you will ever find such rare and improbable objects, and after a few minutes of fossicking about you feel the exercise is pointless and dull. Then you find one. Suddenly your interest is aroused, your imagination piqued, and the chase is on.

And there were plenty of fossils to find. After a long, hot, arid season the first heavy rains had washed a good deal of earth and loose detritus down the slope, exposing underlying layers. Among the flints and pebbles there I found fossilised bones - thin, broken tube-shaped bones; broad joint-like forms that reminded me of shoulder-bones; large, flat-topped molars that over millennia had turned to stone.

There were also rocks there that, with just a bit of fancy, one might see as not quite naturally shaped. Was that an off-cut on that chunk of quartz, or deliberate flaking on that sliver of obsidian? Could the sharp edges of those stones have been used as cutting blades?

I'm no palaeontologist, but in the heat of the moment I was a good fantasist. All these curious stones and bones could not be here by accident. Was it not possible that in some distant age this had been a camp belonging to early man, a curious hominid somewhere between an ape and the homo sapiens of today?

I pictured him hunched down on the slope before a flickering fire. The roughly butchered carcase of a gazelle lay scattered about. His massive jaws crunched bones and he spat the bits out at his feet, but never as he ate did his eyes cease sweeping the darkness around him for danger in the night . . .

If I was allowing myself all sorts of extraordinary imaginings it was, of course, because Olduvai Gorge is an extraordinary place. It was here that, in the middle of the last century, spectacular fossil finds were made, allowing scientists a great leap forward in their understanding of human evolution.

In spite of my enthusiasm, I found my knees growing sore after a couple of hours, and I finally gave up. Enough vague fantasies, I told myself. Some 35km down the gorge at the Olduvai archaeological site I could learn something of the real history of this cradle of man.

So off we headed on the plain above the gorge, a green and grassy expanse dotted with milling herds as far as the eye could see. If I were "handy man", homo habilis, and living a million years ago, how handy would I be, armed with some stone implement, in creeping up behind one of these creatures and killing it for dinner? Not very handy at all, I thought.

But there was at least one modern man who proved that ancient hominids did just that. When Kenyan-born archaeologist Louis Leakey and his wife, Mary, first began visiting Olduvai in the early 1930s, he was convinced that in the stratified layers of the gorge walls lay clues to man's common origins.

When Leakey was scoffed at for offering certain stones as evidence of ancient tool-making, he did not reply with academic argument. He walked down into the gorge, chipped out similar stone tools himself, and caught, killed and butchered wild animals with them. He astounded critics by dismembering antelopes in 10 minutes flat. In the small museum at the visitor centre I gazed at the stone knives, scrapers, pounders and hand-axes that began a technological revolution that continues to this day.

But it took the Leakeys more than 10 minutes to produce the evidence that finally brought them world attention. At the bottom of the gorge I gazed at the place where, 28 long years after beginning their search for early man, Mary Leakey one day in 1959 caught sight of a tiny scrap of bone.

There she went on to find two large hominid teeth, and then the first skull of Zinjanthropus, or Australopithecus boisei, commonly called "Nutcracker man". The discover y of the creature that lived some 1.75m years ago brought the funding the Leakeys needed to further construct man's family-tree. The rest, as I would like to think they say at Olduvai, is pre-history.

That evening, back at Ndutu Camp, I sat down to an elegantly set dinner table. My fellow guests included a New Zealand financial lawyer from Hong Kong and an English marketing couple - they were, all in all, a very modern lot.

Their day had been an adventurous one filled with hippos and lions. And what, they asked cheerfully, had I found?

"Fossils", I replied, expecting to be quizzed for at least a moment on hand axes and the dismembering of small mammals.

"How fascinating," they said, eyes glazing over, and they moved rapidly on to talk of other more amusing subjects - Harry Potter books, the power-steering on Bentley cars, summer holidays in the Dordogne.

I took it amiss at first, and continued eating my p‚tť in silence. Did they not realise that without the talents homo habilis had developed, power-steering would not even exist?

But by the time the banana-toffee pie arrived - a speciality of Ndutu - I had warmed to them. For were we not, after all, one big family? No matter where we came from - London, Hong Kong, or the kitchen of Ndutu camp - did we not have one common ancestor? He lay not far away, in the bottom of Olduvai Gorge.

BONE UP ON THE FACTS

Nicholas Woodsworth's safari was arranged by Tim Best Travel, specialists in tailor-made African holidays. Tel: +44 (0)207-591 0300, e-mail: info@timbesttravel.com Four nights at Nomad Safari's Ndutu Camp, excluding flights and transfers, begins at £1,200 per person. A 12-day Tented Safari in northern Tanzania, including all flights, transfers, food, drink and park fees, costs from £3,250 per person, based on four travelling.

Were two species of early man really one?

Star-Ledger Staff

To further stir things up, Blumenschine colleagues Ron Clarke, a fossil surgeon from South Africa, and Charles Peters of the University of Georgia say other Tanzanian fossils described as Homo habilis really may be something else -- a smaller- brained species, as yet unnamed.

The process of naming species is called taxonomy, and it can produce these kinds of sparks among scientists.

"This problem is not unusual," writes South African researcher Phillip Tobias in a commentary that accompanies Blumenschine's paper in the journal Science.

"We are living at a time when hominin samples from just one or two sites are generating a flurry of new species and genera," asserted Tobias, who helped name Homo habilis in 1964. "Hominin" refers to humanlike primates.

Naming our ancestors is crucial to studying them, said Ian Tattersall, anthropology curator at the American Museum of Natural History. "You'll never understand the play if you don't know who the actors are," he said.

Tattersall welcomes Blumenschine's claims: "This will open the way for a lot of discussion. There's plenty of room for controversy."

There is room because precious little is known about Homo habilis. No complete skeletons have been found; most of what is known comes from a few dozen fragments.

Homo habilis was discovered in 1960 by a Leakey team, which unearthed a lower jaw on the eastern side of Tanzania's Olduvai Gorge, a fossil treasure trove in East Africa. Blumenschine's team made its 1995 find on the western side of this ancient lake.

Scientists with mass spectrometers estimated age based on known decay rates of radioactive isotopes, found in volcanic ash and glass at the site. The technique is accurate within 10,000 years, said Swisher.

Finally, Swisher used a magnetometer to determine the alignment of small magnetic grains within rocks at the excavation site.

Blumenschine, 48, grew up watching Marlin Perkins' "Wild Kingdom" and reading about the Leakeys. He has spent summers at Olduvai Gorge since 1989. His forte is prehistoric tools and their uses for preparing food.

Controversy aside, Blumenschine said he considers his work an antidote to modern strife.

"Here we have something from the very remote past, an ancestor of everybody on the planet," he said. "It helps us to better understand what humans are all about."

Oldupai

All across this land remain the names of places that the Maasai have given them.

Ngorongoro means the place with mountains and gorges.

Oldupai is the wild sisal that grows in the Olduvai gorge, and Siringet is the Maasai word for a vast place.

From the northern edge of the Ngorongoro crater, I follow the 90 meter deep and 50 kilometer long Olduvai gorge west into the Serengeti. The first time I ever came here, I didn't have a map. A bush pilot and filmmaker named AlanRoot drew me a map on a piece of scrap paper. There was a bump on the horizon and a line for a road. He put a dot where the road intersected a river, and that he said was where I would find the airstrip.

This place is not so different from his map. It is simple. There is a sea of yellow, and a sky of blue. Perhaps, it is because the colors are complimentary to each other that makes them so powerful together; the one magnifies the other in a surreal way that makes me feel like I am floating between heaven and earth. Amidst the endless tawny yellow below are the distinctive island kopjies of the Serengeti. These little rock islands are mini ecosystems with birds, lizards, hyraxes, and sometimes, a resident leopard. There are no trees, and you can see the wind flowing like waves across the grass.